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1.
硫酸氢钠催化合成羧酸烯丙酯   总被引:8,自引:0,他引:8  
丁亮中  俞善信  张鲁西 《合成化学》2001,9(5):457-458,472
硫酸氢钠能够代替硫酸作为酯化催化剂。利用-水硫酸氢钠催化合成了甲酸烯丙酯、乙酸烯丙酯、丙酸烯丙酯、丁酸烯丙酯和戊酸烯丙酯,产物用折射率、元素分析和红外光谱表征。研究了硫酸氢钠用量对丙酸烯丙酯收率的影响。  相似文献   

2.
The catalytic activity and regioselectivity were studied of the salenCo(III)OAc complex in the reaction of addition of aliphatic carboxylic acids to a series of terminal epoxides (epichlorohydrin, 1,2-epoxybutane, propylene oxide, tert-butyl glycidyl ether and 2,3-epoxypropyl phenyl ether). The reduction in the activity in the order: acetic > acrylic > methacrylic acid was found. The regioselectivity of the addition was independent on carboxylic acid nature and depended on the nature of the epoxide. The best regioselectivity for the addition to epichlorohydrin was observed. The catalytic activity and regioselectivity of salenCo(III)OAc were compared with those for chromium(III) acetate catalyst.  相似文献   

3.
Conclusions The oxidation of propylene by palladium chloride in glacial acetic acid leads to the formation of isopropenyl acetate, cis-n-propenyl acetate, trans-n-propenyl acetate, the corresponding alkylidene diacetate, and small amounts of allyl acetate.Translated from Izvestiya Akademii Nauk SSSR, Khimicheskaya, No. 12, pp. 2204–2206, December, 1965  相似文献   

4.
采用浸渍法制备MoFe/X(X=SnO_2,ZrO_2,CeO_2,TiO_2,CNTs,MgO)以及MoFe氧化物催化剂用于甘油气-固相催化转化制丙烯醇。通过XRD、BET、XPS、H_2-TPR和NH_3-TPD表征,MoFe主要由晶相Fe_2O_3和Fe_2(MoO_4)_3组成而MoFe/X主要为高分散态的Fe、Mo氧化物(Fe~(3+)、Mo~(6+)),其表面均只存在弱酸中心;所采用载体由于自身性质(比表面积和酸碱性)差异与Mo、Fe氧化物之间存在不同的相互作用,进而有效地调控了MoFe/X的表面弱酸强度、酸浓度和可还原性能。所制备催化剂对甘油制丙烯醇的催化性能(收率)依次为:MoFe/TiO_2MoFe/CeO_2MoFe/ZrO_2MoFe/CNTsMoFe/SnO_2MoFeMoFe/MgO。340°C时,MoFe/TiO_2上甘油的转化率达到83.4%,丙烯醇的选择性和收率分别达到26.7%和22.3%;同时其展现出优于MoFe/CeO_2、MoFe/ZrO_2和MoFe/CNTs的稳定性。甘油转化率与催化剂表面弱酸中心浓度呈正相关性,而丙烯醇的生成则与氧化中心(非酸中心)密切相关。甘油转化率和丙烯醇选择性在MoFe/X上随反应温度变化而呈现相悖的变化趋势。  相似文献   

5.
The chlorohydrination of allyl chloride with chlorine in water was studied at 20–80°C. The effect of the concentration of chloride ions within the range 0–3.6 mol/l on the selectivity of formation of glycerol dichlorohydrins was studied. An equation that relates the selectivity and the concentration of Clwas derived, which adequately describes experimental data. The schemes of parallel and consecutive reactions occurring in the system were suggested. The ratios between the rate constants of the following reactions were found: the reactions of chlorine with water and allyl chloride dissolved in water (k 1/k 4= 4.1 × 10–4), the reaction of allyl chloride with hypochlorous acid and the decomposition of hypochlorous acid (k 2/k 3= 1.7 × 103), and the reactions of the allyl chloride–chlorine complex with a water molecule and Cl(k 5/k 6= 2.9 × 10–2).  相似文献   

6.
1,3-丙二醇具有很高的经济价值,是合成纤维聚对苯二甲酸丙二酯的重要原料。基于甘油甲酸介入法获得的丙烯醇作为平台分子,通过丙烯醇与TiCl4-NaBH4反应,首次实现常温常压下1,3-丙二醇的制备, 为1,3-丙二醇的合成提供了一条新的路径。在最优条件下,1,3-丙二醇的产率68.73%,推测反应机理为:TiCl4和NaBH4发生反应,生成中间体 “BH3”,进而实现了丙烯醇反马氏水合制备1,3-丙二醇。  相似文献   

7.
Ueda T  Konishi H  Manabe K 《Organic letters》2012,14(12):3100-3103
Highly efficient palladium-catalyzed carbonylation of aryl, alkenyl, and allyl halides with phenyl formate is reported. This procedure does not use carbon monoxide and affords one-carbon-elongated carboxylic acid phenyl esters in excellent yields. The reaction proceeds smoothly under mild conditions and tolerates a wide range of functional groups including aldehyde, ether, ketone, ester, and cyano groups. Furthermore, a variety of heteroaromatic bromides can be converted to the corresponding phenyl esters in high yields.  相似文献   

8.
Herein, we report the application of allyl acetate to the palladium‐catalysed dearomatising diallylation of indoles. The reaction can be carried out by using a readily available palladium catalyst at room temperature, and can be applied to a wide range of substituted indoles to provide access to the corresponding 3,3‐diallylindolinines. These compounds are versatile synthetic intermediates that readily undergo Ugi reactions or proline‐catalysed asymmetric Mannich reactions. Alternatively, acylation of the 3,3‐diallylindolinines with an acid chloride or a chloroformate, followed by treatment with aluminium chloride, enables 2,3‐diallylindoles to be prepared. By using ring‐closing metathesis, functionalised spirocyclic indoline scaffolds can be accessed from the Ugi products, and a dihydrocarbazole can be prepared from the corresponding 2,3‐diallylindole.  相似文献   

9.
Synthesis was performed of substituted 2-propanols based on glycidyl phenyl and glycidyl allyl ethers, Also some acetic acid esters were prepared.  相似文献   

10.
Conclusions The oxidation of butene-1 by palladium chloride in glacial acetic acid leads to the formation of a mixture of complex alkenyl esters: butene-1-ol-3 acetate, butene-1-ol-2 acetate, the acetates of trans- and cis-butene-2-ols-2, and the acetates of trans- and cis-butene-2-ols-1.  相似文献   

11.
Poly(allyl stearate) and selected copolymers and terpolymers modified by allyl stearate were investigated in this work. The systems selected and studied over a wide range of composition, included copolymers with vinyl stearate and with vinyl chloride, and terpolymers containing vinyl chloride and allyl stearate, modified further by vinyl stearate or vinyl acetate. Copolymers of allyl stearate and vinyl stearate were studied incrementally across the range of composition. In the ester copolymers the effect of degradative chain transfer on crystallization and solution properties was studied. A relation was obtained between intrinsic viscosities and number-average molecular weights; a shift in molecular weight distribution with increase in allyl component was demonstrated. The crystallinity contributed by the side chains was shown to be characterized by isomorphic replacement regardless of molecular weight. Mechanical properties of internally plasticized copolymers of allyl stearate and vinyl chloride, in a limited composition range, were compared with corresponding data for copolymers of vinyl stearate and vinyl chloride. While molecular weight reduction of the allylic copolymers exceeded that for the vinyl ester system, the effect, in the useful plasticization composition range, was not enough to grossly affect ultimate properties. The glass transitions of the hypothetical amorphous homopolymers of both fatty esters were estimated to be the same. Because this Tg was low (ca. ?110°C), only relatively small mole fractions of allyl stearate were needed for effective plasticization. Isochronal temperature–composition diagrams also showed both systems to be essentially identical, but marked differences were found for diluent mixtures incorporating di-2-ethylhexyl phthalate (DOP). An empirical equation, previously derived, adequately predicted the decline in degree of polymerization with increase in allyl stearate between the limits of the respective homopolymers for all copolymers studied. Terpolymers followed the trends of the copolymers and offered no special property advantage.  相似文献   

12.
The title compounds, 7a-e, were obtained by direct acid catalyzed condensation of diethyl malonate and triethyl ortho formate, with the corresponding aniline in acetic anhydride. In the absence of acetic anhydride amido esters 8a-e were formed.  相似文献   

13.
The synthesis and polymerization of seven epoxy polymer precursors which contained the siloxane linkage in varying structural arrangements was carried out. The polymers prepared from such precursors have utility as embedding compounds for electrical circuits. Polymerization of these epoxy intermediates with siloxane-containing diamines resulted in solid, thermosetting materials for which dielectric data were obtained. Dielectric constants of 3.1 were measured at 1 keps for polymers prepared by polymerization of 1,9-bis[p-(2,3-epoxypropyl)phenyl]decamethylpentasiloxane with 1,3-bis(p-am-inophenoxy)tetramethyldisiloxane, whereas polymers derived from 1,4-bis{[p-(2,3-epoxypropyl)phenyldimethylsiloxy]dimethylsilyl}benzene and the same diamine were characterized by slightly higher dielectric constants and a high degree of toughness, being nonbrittle at ?50°C.  相似文献   

14.
The reaction of (2,2-dimethylhydrazino)succinic acid ester with allyl and phenyl isothiocyanates leads to esters of 1-substituted (3-dimethylamino-5-oxo-2-thioxo-4-imidazolidinyl)acetic acids, which in protic solvents undergo a slight degree of elimination of dimethylamine to give esters of 1-substituted (5-oxo-2-thioxoimidazolidin-4-ylidene)acetic acids. The structure of methyl (1-allyl-5-oxo-2-thioxoimidazolidin-4-ylidene)acetate was proved by x-ray diffraction analysis.Communication 3 from the series Derivatives of hydrazino carboxylic acids, See [1] for communication 2.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1219–1223, September, 1987.  相似文献   

15.
The kinetics of graft polymerization of vinyl acetate on allyl chitosan samples with varied content of allyl groups, initiated with ammonium peroxodisulfate, was studied.  相似文献   

16.
苯氧乙酸烯丙酯的合成   总被引:1,自引:0,他引:1  
孟庆朝  董玉环 《合成化学》2004,12(2):201-203
对苯酚和氯乙酸的Williamson反应加以改进,使苯氧乙酸的收率达到95.4%。并以苯氧乙酸和烯丙醇为原料,活性碳负载磷钨酸为催化剂,合成了苯氧乙酸烯丙酯。考察了两个反应的主要影响因素。  相似文献   

17.
A simple and practical synthesis of the benzyl, allyl, and 4-nitrobenzyl esters of N-[2-(Fmoc)aminoethyl]glycine is described starting from the known N-(2-aminoethyl)glycine. These esters are stored as stable hydrochloride salts and were used in the synthesis of peptide nucleic acid monomers possessing bis-N-Boc-protected nucleobase moieties on the exocyclic amino groups of ethyl cytosin-1-ylacetate, ethyl adenin-9-ylacetate and ethyl (O(6)-benzylguanin-9-yl)acetate. Upon ester hydrolysis, the corresponding nucleobase acetic acids were coupled to N-[2-(Fmoc)aminoethyl]glycine benzyl ester or to N-[2-(Fmoc)aminoethyl]glycine allyl ester in order to retain the O(6) benzyl ether protecting group of guanine. The Fmoc/bis-N-Boc-protected monomers were successfully used in the Fmoc-mediated solid-phase peptide synthesis of mixed sequence 10-mer PNA oligomers and are shown to be a viable alternative to the currently most widely used Fmoc/Bhoc-protected peptide nucleic acid monomers.  相似文献   

18.
The successful Pd-catalysed allylation of 2-phenylpropanal with allyl alcohol in ionic liquid is described and thus a simplier reaction composition catalytic system than in THF is possible. On the other hand, the Pd-catalyzed α-allylation of the same substrate with allyl acetate or allyl ethyl carbonate is proceeding nicely in ionic liquids. Allylation of different carbonyl derivatives was studied and it was found that the reaction is restricted to carbonyl derivatives from which a carbanion stabilized by an adjacent aromatic ring can be formed.  相似文献   

19.
We report a short synthetic route for synthesizing 2,3-substituted piperazine acetic acid esters. Optically pure amino acids were efficiently converted into 1,2-diamines that could be utilized to deliver the title 2,3-substituted piperazines in five steps with a high enantiomeric purity. The novel route facilitated, for the first time, the synthesis of 3-phenyl substituted-2-piperazine acetic acid esters that were difficult to achieve using other methods; however, in this case, the products underwent racemization.  相似文献   

20.
Summary. The successful Pd-catalysed allylation of 2-phenylpropanal with allyl alcohol in ionic liquid is described and thus a simplier reaction composition catalytic system than in THF is possible. On the other hand, the Pd-catalyzed α-allylation of the same substrate with allyl acetate or allyl ethyl carbonate is proceeding nicely in ionic liquids. Allylation of different carbonyl derivatives was studied and it was found that the reaction is restricted to carbonyl derivatives from which a carbanion stabilized by an adjacent aromatic ring can be formed.  相似文献   

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